True, but it's correctible in software, or by using a UV2A filter. There's not correcting for 2/3 stop slower.

But there is evidence suggesting it might not be 2/3 stops slower. The difference in background blur is so minor you have to look for it, and the camera was selecting a shutter speed that was 20% slower at the same aperture with the Panasonic lens to get the same exposure with the Olympus lens. I'm sure there will be more comparisons, but the initial findings were surprising.

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Completely infatuated with the "OMG"

It's common in fast lenses that wider apertures don't translate completely to faster exposures. But the PL is still faster and it does still have narrower DOF, which I think will turn out to be less subtle than Mr. Wong would have you believe....